The present invention relates to a carburetor arrangement for an internal combustion engine in a manually guided implement, such as a power chainsaw, a cut-off machine, or the like.
EP 0 786 591 discloses a carburetor arrangement that includes a scavenging pump and an injection pump as the actual starting aid. By actuating the injection pump, fuel can be introduced into the intake channel prior to starting the engine. As a result, an adequate supply of fuel to the internal combustion engine is intended to be achieved already for the first ignitions without a choke. The injected quantity of fuel is, however, consumed as the engine starts.
An internal combustion engine is generally started with the choke valve closed. If, after start-up of the engine, the choke valve is opened too rapidly, the mixture can become too lean, especially with a cold engine. As a consequence, the engine stalls. A renewed starting with the choke closed can lead to the supply of too much fuel to the combustion chamber. Numerous further attempts are then necessary in order to start the engine.
It is therefore an object of the present invention to provide a carburetor arrangement of the aforementioned general type that provides an adequate amount of fuel to an internal combustion engine during the starting and run-up phases.